Fan control scripts
Contents
Fan enable/disable scripts
sh script example
#!/bin/sh
MAXTEMP=50
while [ 1 ];
do
fan=no
for temp in `sed s/temperatures:// < /proc/acpi/ibm/thermal`
do
test $temp -gt $MAXTEMP && fan=yes
done
command='disable'
test "$fan" = "yes" && command='enable'
echo $command > /proc/acpi/ibm/fan
sleep 20
done
sh script with more features
#!/bin/sh
# fan control-script
#
# based upon ibm-acpi 0.11 (experimental=1 !)
#
# eliminates anoying "fan always on" in battery mode
# works with hysteresis (DELTA) so that always-turn-on/turn-off is avoided
# fan acivates at MAXTEMP and cools down CPU, GPU etc. to MAXTEMP-DELTA than the fan is turned off
# furthermore detects if AC is on and gives back fan control to default behaviour than
#
# one can change MAXTEMP and DELTA to individual values
# but take care of your THINKPAD don`t melt it!
#
# have fun!
# mk 05.05.05
MAXTEMP=51
DELTA=4
SWITCHTEMP=$MAXTEMP
#make sure the script doesn't leave the fan off on error
trap "echo enable > /proc/acpi/ibm/fan" EXIT
while [ 1 ];
do
for ac in `sed s/state:// < /proc/acpi/ac_adapter/AC/state`
do
if [ "$ac" = "off-line" ]; then
fan=no
for temp in `sed s/temperatures:// < /proc/acpi/ibm/thermal`
do
test $temp -gt $SWITCHTEMP && fan=yes
done
if [ "$fan" = "yes" ]; then
command='enable'
SWITCHTEMP=`expr $MAXTEMP - $DELTA`
else
SWITCHTEMP=$MAXTEMP
command='disable'
fi
else # ac-adapter on -> set fan control to standard behaviour
command='enable'
fi
echo $command > /proc/acpi/ibm/fan
sleep 15
done
done
sh script with extra safety functionality
ibm_acpi usually works well. But to rely on it completely, this script provides some extra safety functionality:
- It catches various signals and turns the fan on before it quits.
- It turns off the fan under very strict conditions, leaving it on when unexpected errors occur.
#!/bin/sh
# july 2005 Erik Groeneveld, erik@cq2.nl
# It makes sure the fan is on in case of errors
# and only turns it off when all temps are ok.
IBM_ACPI=/proc/acpi/ibm
THERMOMETER=$IBM_ACPI/thermal
FAN=$IBM_ACPI/fan
MAXTRIPPOINT=65
MINTRIPPOINT=60
TRIPPOINT=$MINTRIPPOINT
echo fancontrol: Thermometer: $THERMOMETER, Fan: $FAN
echo fancontrol: Current `cat $THERMOMETER`
echo fancontrol: Controlling temperatures between $MINTRIPPOINT and $MAXTRIPPOINT degrees.
# Make sure the fan is turned on when the script crashes or is killed
trap "echo enable > $FAN; exit 0" HUP KILL INT ABRT STOP QUIT SEGV TERM
while [ 1 ];
do
command=enable
temperatures=`sed s/temperatures:// < $THERMOMETER`
result=
for temp in $temperatures
do
test $temp -le $TRIPPOINT && result=$result.Ok
done
if [ "$result" = ".Ok.Ok.Ok.Ok.Ok.Ok.Ok.Ok" ]; then
command=disable
TRIPPOINT=$MAXTRIPPOINT
else
command=enable
TRIPPOINT=$MINTRIPPOINT
fi
echo $command > $FAN
# Temperature ramps up quickly, so pick this not too large:
sleep 5
done
Variable speed control scripts
While the above scripts only toggle the fan on and off, the following scripts also sets the fan speed according to sytem temperatures. In addition, they include a hack for preventing the annoying fan pulsing that occurs on some systems. Note that the fan levels, thresholds and anti-pulsing hacks are system-specific, so you may need to adjust them.
bash script with fine control over fan speed (for unpatched kernels)
The following requires only ibm-acpi 0.11 or higher (e.g., as found in kernel 2.6.14 and higher) with the experimental=1 module parameter. It supports (optional) daemon mode and logging to syslog.
#!/bin/bash
# This script dynamically controls fan speed on some ThinkPad models
# according to user-defined temperature thresholds. It implements its
# own decision algorithm, overriding the ThinkPad embedded
# controller. It also implements a workaround for the fan noise pulse
# experienced every few seconds on some ThinkPads.
#
# WARNING: This script relies on undocumented hardware features and
# overrides nominal hardware behavior. It may thus cause arbitrary
# damage to your laptop or data. Watch your temperatures!
#
# This file is placed in the public domain and may be freely distributed.
LEVELS=( 0 2 4 7) # Fan speed levels
UP_TEMPS=( 52 60 68 ) # Speed increase trip points
DOWN_TEMPS=( 48 56 64 ) # Speed decrease trip points
ANTIPULSE=( 0 1 0 0) # Prevent fan pulsing noise at this level
# (this also prevents fan speed updates)
IBM_ACPI=/proc/acpi/ibm
HDAPS_TEMP=/sys/bus/platform/drivers/hdaps/hdaps/temp1
PID_FILE=/var/run/tp-fancontrol.pid
INTERVAL=3
VERBOSE=true
DRY_RUN=false
DAEMONIZE=false
AM_DAEMON=false
KILL_DAEMON=false
SYSLOG=false
LOGGER=/usr/bin/logger
usage() {
echo "Usage: $0 [OPTION]..."
echo
echo "Available options:"
echo " -t test mode"
echo " -q quiet mode"
echo " -d daemon mode, go into background (implies -q)"
echo " -l log to syslog"
echo " -p pid file location for daemon mode, default: $PID_FILE"
echo " -k kill daemon (ignores all but -p)"
exit 1
}
while getopts 'qtdlp:kh' OPT; do
case "$OPT" in
t) # test mode
DRY_RUN=true
;;
q) # quiet mode
VERBOSE=false
;;
d) # go into background and daemonize
DAEMONIZE=true
;;
l) # log to syslog
SYSLOG=true
;;
p) # different pidfile
PID_FILE="$OPTARG"
;;
k) # kill daemon
KILL_DAEMON=true
;;
h) # short help
usage
;;
\?) # error
usage
;;
esac
done
[[ $OPTIND -gt $# ]] || usage # no non-option args
# no logger found, no syslog capabilities
$SYSLOG && [[ ! -x $LOGGER ]] && SYSLOG=false
if $DRY_RUN; then
echo "$0: Dry run, will not change fan state."
VERBOSE=true
DAEMONIZE=false
fi
thermometer() { # output list of temperatures
read X Y < $IBM_ACPI/thermal
if ! [[ "$X" == "temperatures:" ]]; then
echo "$0: Bad temperatures: $X $Y" >&2
exit 1
fi
echo -n "$Y ";
[ -r $HDAPS_TEMP ] && echo -n "`cat $HDAPS_TEMP` "
return 0
}
speedometer() { # output fan speed RPM
sed -n 's/^speed:[ \t]*//p' $IBM_ACPI/fan
}
setlevel() { # set fan speed level
$DRY_RUN || echo 0x2F $1 > $IBM_ACPI/ecdump
}
cleanup() { # clean up after work
$AM_DAEMON && rm -f $PID_FILE 2> /dev/null
$SYSLOG && $LOGGER -t "`basename $0`[$$]" \
"Shutting down, switching to automatic fan control"
$DRY_RUN || echo enable > $IBM_ACPI/fan
}
control_fan() {
# Enable the fan in default mode if anything goes wrong:
set -e -E -u
trap "cleanup; exit 2" HUP INT ABRT QUIT SEGV TERM
trap "cleanup" EXIT
IDX=0
MAX_IDX=$(( ${#LEVELS[@]} - 1 ))
SETTLE=0
FIRST=true
$SYSLOG && $LOGGER -t "`basename $0`[$$]" "Starting dynamic fan control"
# Control loop:
while true; do
TEMPS=`thermometer`
$VERBOSE && SPEED=`speedometer`
# Calculate new level
NEWIDX=$IDX
DOWN=$(( IDX > 0 ))
for TEMP in $TEMPS; do
# Increase speed as much as needed
while [[ $NEWIDX -lt $MAX_IDX ]] &&
[[ $TEMP -ge ${UP_TEMPS[$NEWIDX]} ]]; do
(( NEWIDX ++ ))
DOWN=0
done
# Allow decrease (by one index)?
if [[ $DOWN == 1 ]] &&
[[ $TEMP -gt ${DOWN_TEMPS[$(( IDX - 1 ))]} ]]; then
DOWN=0
fi
done
if [[ $DOWN == 1 ]]; then
NEWIDX=$(( IDX - 1 ))
fi
# Transition
$FIRST && OLDLEVEL=unknown || OLDLEVEL=${LEVELS[$IDX]}
NEWLEVEL=${LEVELS[$NEWIDX]}
$VERBOSE && echo "Temps: $TEMPS Fan: $SPEED Level: $OLDLEVEL->$NEWLEVEL"
$SYSLOG && [[ $OLDLEVEL != $NEWLEVEL ]] &&
$LOGGER -t "`basename $0`[$$]" "Changing fan level: $OLDLEVEL->$NEWLEVEL"
setlevel $NEWLEVEL
sleep $INTERVAL
# If needed, apply anti-pulsing hack after a settle-down period:
if [[ ${ANTIPULSE[${NEWIDX}]} == 1 ]]; then
if [[ $NEWLEVEL == $OLDLEVEL ]]; then
if [[ $SETTLE -ge 0 ]]; then
(( SETTLE -= INTERVAL ))
else
setlevel 0x40 # disengaged
sleep 0.5
fi
else
SETTLE=6
fi
fi
IDX=$NEWIDX
FIRST=false
done
}
if $KILL_DAEMON ; then
if [ -f $PID_FILE ]; then
set -e
DPID="`cat $PID_FILE`"
kill "$DPID"
rm "$PID_FILE"
$VERBOSE && echo "Killed process $DPID"
else
$VERBOSE && echo "Daemon not running."
exit 1
fi
elif $DAEMONIZE ; then
if [ -e "$PID_FILE" ]; then
echo "$0: File $PID_FILE already exists, refusing to run."
exit 1
else
AM_DAEMON=true VERBOSE=false control_fan 0<&- 1>&- 2>&- &
echo $! > "$PID_FILE"
exit 0
fi
else
control_fan
fi
The authors of the script (Thinker and Spiney) disclaim all warranty for this script, and release it to the public domain (meaning you may use it and further distribute it under any terms you wish, including incorporating it into other software).
bash script with fine control over fan speed (requires kernel patch)
The following is a simpler patch (without extra features like daemon mode and logging). It requires the patch for controlling fan speed.
#!/bin/bash
# This script dynamically controls fan speed on some ThinkPad models
# according to user-defined temperature thresholds. It implements its
# own decision algorithm, overriding the ThinkPad embedded
# controller. It also implements a workaround for the fan noise pulse
# experienced every few seconds on some ThinkPads.
#
# The script requires the ibm_acpi patch at
# http://thinkwiki.org/wiki/Patch_for_controlling_fan_speed
#
# WARNING: This script relies on undocumented hardware features and
# overrides nominal hardware behavior. It may thus cause arbitrary
# damage to your laptop or data. Watch your temperatures!
#
# This file is placed in the public domain and may be freely distributed.
LEVELS=( 0 2 4 7) # Fan speed levels
UP_TEMPS=( 52 60 68 ) # Speed increase trip points
DOWN_TEMPS=( 48 56 64 ) # Speed decrease trip points
ANTIPULSE=( 0 1 0 0) # Prevent fan pulsing noise at this level
# (this also prevents fan speed updates)
IBM_ACPI=/proc/acpi/ibm
FAN=$IBM_ACPI/fan
INTERVAL=3
VERBOSE=true
DRY_RUN=false
[[ "$1" == "-t" ]] && { DRY_RUN=true; echo "$0: Dry run, will not change fan state."; }
# Enable the fan in default mode if anything goes wrong:
set -e -E -u
$DRY_RUN || trap "echo enable > $FAN; exit 0" EXIT HUP INT ABRT QUIT SEGV TERM
thermometer() { # output list of temperatures
read X Y < $IBM_ACPI/thermal
[[ "$X" == "temperatures:" ]] || {
echo "$0: Bad temperatures: $X $Y" >&2
exit 1
}
echo "$Y";
}
speedometer() { # output fan speed
cat $FAN | sed '/^speed/!d; s/speed:[ \t]*//'
}
IDX=0
MAX_IDX=$(( ${#LEVELS[@]} - 1 ))
SETTLE=0
while true; do
TEMPS=`thermometer`
$VERBOSE && SPEED=`speedometer`
# Calculate new level
NEWIDX=$IDX
DOWN=$(( IDX > 0 ))
for TEMP in $TEMPS; do
# Increase speed as much as needed
while [[ $NEWIDX -lt $MAX_IDX ]] &&
[[ $TEMP -ge ${UP_TEMPS[$NEWIDX]} ]]; do
(( NEWIDX ++ ))
DOWN=0
done
# Allow decrease (by one index)?
if [[ $DOWN == 1 ]] &&
[[ $TEMP -gt ${DOWN_TEMPS[$(( IDX - 1 ))]} ]]; then
DOWN=0
fi
done
if [[ $DOWN == 1 ]]; then
NEWIDX=$(( IDX - 1 ))
fi
# Transition
OLDLEVEL=${LEVELS[$IDX]}
NEWLEVEL=${LEVELS[$NEWIDX]}
$VERBOSE && echo "tpfan: Temps: $TEMPS Fan: $SPEED Level: $OLDLEVEL->$NEWLEVEL"
$DRY_RUN || echo level $NEWLEVEL > $FAN
sleep $INTERVAL
# If needed, apply anti-pulsing hack after a settle-down period:
if [[ ${ANTIPULSE[${NEWIDX}]} == 1 ]]; then
if [[ $NEWLEVEL == $OLDLEVEL ]]; then
if [[ $SETTLE -ge 0 ]]; then
(( SETTLE -= INTERVAL ))
else
$DRY_RUN || echo level disengaged >> $FAN
sleep 0.5
fi
else
SETTLE=6
fi
fi
IDX=$NEWIDX
done
The author of the script disclaims all warranty for this script, and releases it to the public domain (meaning you may use it and further distribute it under any terms you wish, including incorporating it into other software).
Init scripts
Init script example
#! /bin/sh
N=/etc/init.d/fan
set -e
case "$1" in
start)
# make sure privileges don't persist across reboots
if [ -d /var/run/fan ] && [ "x`ls /var/run/fan`" != x ]
then
touch -t 198501010000 /var/run/fan/*
fi
fan.sh & # Script from above
;;
stop|reload|restart|force-reload)
killall fan.sh
echo enable > /proc/acpi/ibm/fan
;;
*)
echo "Usage: $N {start|stop|restart|force-reload}" >&2
exit 1
;;
esac
exit 0
Init script example for gentoo
Assume one of the above control scripts is /usr/sbin/ibm-fancontrold, for gentoo use the following init script in /etc/init.d/ibm-fancontrol. Copy the script to /etc/init.d/ibm-fancontrol, then do
# rc-update add ibm-fancontrol default
This will add the init script to the default runlevel.
#!/sbin/runscript
# 2005 Gilbert Tiefengruber
# Distributed under the terms of the GNU General Public License v2
# IBM Fancontrol init script for IBM Thinkpad laptops (tested with R50)
# This init script was written for gentoo 2005.1, kernel 2.6.12
# You need the ibm_acpi kernel module version 0.11 or greater
# load the module with experimental=1 to enable the fan controls
depend() {
need localmount
}
checkconfig() {
if [ ! -e /proc/acpi/ibm/fan ]; then
eerror "The ibm_acpi module must be loaded with (experimental=1)"
return 1
fi
}
start() {
checkconfig || return 1
ebegin "Starting ibm-fancontrold"
start-stop-daemon --quiet -p /var/run/ibm-fancontrold.pid -m -b --start -a /usr/sbin/ibm-fancontrold
eend ${?}
}
stop() {
ebegin "Stopping ibm-fancontrold"
start-stop-daemon --stop --quiet -p /var/run/ibm-fancontrold.pid
eend ${?}
}
Other
fanctrld
fanctrld is a daemon (written in C) that controls the Thinkpad's fan. The basic approach is to monitor both temperature and fan speed. The fan is enabled when a certain temperature is exceeded, and disabled when the BIOS slows down the fan below a certain speed.
See also
- For a Windows program with functionality similar to these scripts, see the Thinkpad Fan Noise Problem: Light at the End of the Tunnel forum discussion at thinkpads.com.
